Instrument for drawing irregular curves



(No Model.)

0. W. REEVES. INSTRUMENT .EoR DRAWING IRREGULAR CURVES, ELLIPsEs, &o.No. 434,465. Patented Aug. 19, 1890.

Imam/tor,-

UNITED STATES PATENT OFFICE.

CHARLES WV. REEVES, OF BOSTON, MASSACHUSETTS.

INSTRUMENT FOR DRAWING IRREGULAR CURVES, ELL|PSES, &O.

SPECIFICATION forming part of Letters Fatent No. 434,465, dated August19, 1890.

Application filed October 3, 1887. Serial No, 251,375.v (No model.)

To all whom it may concern:

Be it known that I, CHARLES W. REEVES, of Boston, in the county ofSuffolk and State of Massachusetts, have invented certain new and usefulImprovements in Instruments for Drawing Irregular Curves, Ellipses,Ovals, &c., of which the followingisafull, clear, and exact description.

This instrument for describing lines, irregularly-curving ellipses,ovals, &c., consists of a horizontal and fiat plate as a pattern or formhaving a surrounding edge of a given outlinefor illustration, that of anellipse or oval and attached to a fixed post or stud concentrically orotherwise suitably locatedin combination with an arm radially to andadapted to swing about the axis of said post, a sleeve on said arm andfree to slide lengthwise thereof, a holder .to receive a markersuch as apoint, pencil, pen, &c.and placed upon and adjustable lengthwise of saidsleeve, and means to confine said sleeve toabearing against the edge ofsaid pattern, allowing it to move in toward and out from the axis of theswing of the arm carrying said sleeve, all

' substantially as hereinafter described.

In the drawings, forming part of this specification, Figure 1 is a faceview of the instrument. Fig. 2 is an edge view. Fig. 3 is across-section, line 3 3, Fig. 1; Figs. 4, 5, 6, and 7, detail views, aswill hereinafter appear.

In the drawings, A represents the patternplate and or its edge, shown asof the outline of an ellipse.

B is a post or stud fixed concentrically upon the pattern-plate A.

O is an arm, havinga collar 1) surrounding post B and free to swingthereon, the arm extending radially from the axis of the post and of theswing of said arm. The arm 0, preferably, is made round and it may beany desired length.

F is a tubular sleeve on arm 0 and free to slide lengthwise thereof, andhaving a lip 12 near its inner end and on one side by which to rest itagainst the edge a of the patternplate, the sleeve in its portion beyondsaid lip resting upon the top of the pattern-plate.

G is a collar loosely surrounding sleeve F and free to slide thereon, itbeing secured in place by means of a milled-head binding-screw dscrewingthrough it and setting and binding against the sleeve.

K is an endless elastic band passing about and in the notch f of thenotched stud L of the sleeve F, and g is a groove surrounding the stud Bof the pattern-plate.

In the use of the instrument described the.

pattern-plate is first suitably located and the marking-tool H is thenadjusted to the proper distance, on which the pattern-plate being firmlyheld against displacement, the marking-toolis then swung around the axisof the stud B, causing the marking-tool to describe a curvilinear line,during which the sleeve F, carrying the holder for said tool, is held upto and the tool thereby made to follow the edge a of the pattern plate Aby the elasticity of the band K, connecting said sleeve to said stud, ashas been described.

'lhreo lines having difierent curvilinear directions are illustrated,dotted in the drawings, as instances of lines which can be described bythe instrument properly adjusted for each, but obviously there areothers; and, again, by using pattern-plates of various outlines thedirection-of curves which the instrument is capable of describing may bevaried almost without limit.

Having thus described my invention, What I claim, and desire to secureby Letters Patent, is-* Aninstrum ent for describingirregular lines,composed of a pattern-plate A, an arm 0, swinging around a fixed axis ofsaid plate, a tubular sleeve F, sliding lengthwise on said arm, atool-holder G H, lengthwise adjustable on said sleeve, and means forconfining said sleeve to the edge of said pattern-plate, substantiallyas described, for the purpose specified.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

CHARLES W. REEVES.

